It's less painful to bite your tongue.

Everyone has a bad day once in a while. At these times you need to remember the old saying "If you don't have anything nice to say then don't say anything at all". These are times when biting your tongue is less painful then the consequences of your words. Whoever said words can never hurt you was wrong. And once you say them out loud or in cyberspace ink they are permanent so you can't take them back. Just because it suddenly pops up in your mind doesn't mean it. Should fly out of your mouth.